YOU SAID:

I have four dogs, which I found on my trip to Ireland last summer

INTO JAPANESE

私は去年の夏にアイルランドに行ったときに見つけた4匹の犬を飼っています

BACK INTO ENGLISH

I have four dogs that I found when I went to Ireland last summer

INTO JAPANESE

去年の夏にアイルランドに行ったときに見つけた犬が4匹います

BACK INTO ENGLISH

I have four dogs that I found when I went to Ireland last summer